brush



April 12, 1932;

A. P. BRUSH BRAKE MECHANISM Original Ffiled July 16, 1923 .2 Sheets-Sheet .1

anvenio'z v )4 14M: DAN-DBMS}? allozneq April 12, 1932. A. p. BRUSH Re.18,423

BRAKE MECHANISM Original Filed July 16, 1923 2 Sheets-Sheet 2 anvemto'tlleissued. Apr. 12, 1932 I 4 UNITED" STA-res I Re.

A 'ENT OFHCE Original NIL-1,652,757, dated December 13, 1927, Serial No.651,8 69, filed July 16, 1928. Application for reissue filed January 9,1928. Serial No. 245,597.

. The invention relates to vehicle brake mechanisms and it is theprimary objeet of the invention to obtain a simple and inexpensiveConstruction. It is the further object to 15 obtain certain advantagesas hereinafter set forth. I

In the drawings: Figure 1 is a side elevation of a brake of my improvedconstruction 10 Figure 2 is a similar view sli'ghtly modified;

Figure 3 is a cross section of the construc-- tion shown in Figure 2Figure at is a view similar to Fig.2 of still another modification. y

In the present state of the art brake mechanisms are of two generaltypes,in one of which a rigid brake shoe is moved radially into contactwith the'brake drum, while in the other a flexible brake band is movedcircumferentially 'into contact with the druni. With the first type thearc of contact is less than 180, whilewith the secondtypethe friction ofthe portions of the band initially contacting with the drum may cause,in the case of an external brake, a wrapping eflect,

or, inthe case of, an internal brake, an unwrapping efi'ect which willassist in applying. braking pressure,-- thereby {reducing the amountofpower required. On the other .BOhand, with the first type the amount ofmovement required for setting the brakes 'or for compensating-for wearis approximate 1y, one-sixth the amount required for the circumferentialmovement of the flexible band also a simpler construction of operatingmechanism can be employed. My improved construction combines theadvantages and eliminates the defects of both.

. types above referred to. This isac'com phs'hed; first, by employing aband having a flexible portion which is movable by a wrapping -orunwrapping movement into full con that with the drum ;second, byactuating the band radially instead of circumferentially so.

as to reducethe amountof movement required; third, by providing a rigidsegment which is preferably directly actuated by the radial movement to.contact with the drum 1 v and which prevents excessive wear at the pointof application of said radial-pressure.

usual linin ends with anges or shoulders D andD for- As a result a highbraking torque may bebrakes, I have specifically illustrated only itsapplication to an internal brake. As shown in Figure 1, A' is the brakedrum, B the brake band or ring, out through at one side .of the drum toform separable ends, and having the C and provided at its opposite 1Sapplicable to various constructions of engaging anchoring means such asa stationary abutment E. Diametrically opposite the abutment E the bandis reinforced to be substant-ially rigid by a comparatively rigidsegmental member F, which as shown is approximately' 90. ,To apply thebrake the member -F is moved radially towards the drum A and thefriction produced by contact with the drum will cause a circumferentialmovement of the band which is resistedat one' end by the shoulder D or'D,-according to the direction of rotation of the drum. As a consequence,

.an outward radial pressure is developed in each portion of the bandbetween the abut F ment and the further end of the ri 'd section, whichwill produce a smooth raking efiect and-will uniformly distribute-thewear. The function of thefrlgid section F is to avoid localizing thewear due to the initialfrictional engagement and to dis'tributethis wearuniformly over the whole extent of the ri id segment. Furthermore, byreason of the surface pf the band is brought into action.

same normally out of contact with the drum,

such as and uid'es, such as H. The radial.

Fi re 1, or by the crank-K and link L, as indi dated in Figure 2. Withthe latter; construction two retracting springs G and G are shown. e

The construction shown in Figure 4 is simithis rigid segment,approximately 125? of j pressure upon t e member F may be applied I V byany suitable means, such as the eccentric Ioperated' by a rock armJ, asindicated ii lar to that shown in Figures 1 and 2 with the exceptionthat a rockable stop M is substituted for the rigid stop E. As shown,this stop M is pivotally mounted at N and extends between 5 the endshoulders D and D at the ends of the brake band. With this construction,when torque is developed inth'e band by the initial frictionalengagement of the rigid portion, the whole band will rotate moving withit the m member M. This member will, however, op-

erate as a lever pf the third class, whilch byits chan 'n an arity willenlar e t 1e space betwe dn the i butments D and and will developoutward radial pressure in the whole of the band. Thus the addedadvantage is obtained of bringing the entire band into action duringeither direction of rotation of the drum.

What I claim is a 1. The combination with a brake drum, of

a flexible internal split brake band therein, an abutment between theends of said band, a

- rigid segment in said band intermediate the .a flexible brake bandadjacent thereto, an

abutmentfor one end of said band, means for directly applying outwardradial pressure to a point in said band spaced from said abut- I mentpoint while permitting circumferential movement of the hand between saidpoints, whereby the initial friction will develop in said band radialpressure against the drum at all points between said abutment and pres-0 sure applying point.

The combination with a brake drum, of a. flexible brake .band adjacentthereto, an abutment for one point in said band, a rigid segment in saidband spaced from said abutment point, andmeans for directly applyingoutward radial pressure to said rigid segment while permitting freedomfor circumferential movement, for the purpose described.

3. The combination with a brake drum, of a. flexible split brake bandadjaceht thereto, torque-taking means for the ends of said split band,and means for directly applying outward radial pressure to said band ata point intermediate the ends thereof while permitting freecircumferential movement in either direction, for the purpose described.v 4. The combination with a brake drum, of

a flexible split brake band adjacent thereto, torque-taking means forthe ends of said band at one point therein, a rigid segment in saidbandintermediate the ends thereof, and means for directly applyingoutward radial pressure to said segment while permitting reecircumferential movement thereof in either direction.

ends thereof, and means for applying out ward radial pressure to saidrigid segment comprising a crank and link, permitting freecircumferential movement in. either direction.

7. The combination with a brake drum, of a split flexible brake bandadjacent thereto, an abutment between the ends of'saidband, a rigidsegment in said band intermediate the ends thereof, means for directlyapplying radial pressure. to said rigid segment while permitting freecircumferential movement thereof, and means actuated by thecircumferential movement of the band for relatively moving the endsthereof, whereby radial pressure is developed in all portions of theband. 7

8. The combination with a brake drum, of

a split flexible brake band therein, a rigid segment in said bandintermediate the ends thereof, means for directly applying radialpressure to said segment, perm'ittingfree circumferential movementthereof, and a rock- 5. The combination with a brake drum, of V aflexible internal split brake band therein, an abutment arranged betweenthe ends of 60 said band, a segment in said band intermediate the endsthereof, and means for directly applying outward radial pressure to saidrigid segment, for the purpose de-- scribed.

)5 6. The combination with a brake drum, of

able abutment member between the ends of said band actuatedby thecircumferential movement thereof to spread. said ends and to developradial pressure in all portions of the band. a o t 9; The combinationwith a brake drum, of a flexible split brake band adjacent thereto,torque-taking means for the ends of said split band, means for directlyapplying outward radial pressure to said band at a point intermediatethe ends thereof while permitting free circumferential movement ineither direction, and guiding. means for said flexible brake bandintermediate said torque-taking means and pressure applying means.

10. The combination with a brake drum, of a flexible split brake bandadjacent thereto, torque-taking means for the ends of said split band, arigid segment in said band intermediate the ends thereof, guiding meansfor a said hand between said torque-taking means and said rigidsegment,-means for directly appl ing outward radial pressure to said.rigi' segment while permitting freedom for circumferential movement, andresilient .retracting means connected to said band.

11. The combination with a brake drum, of a flexible internal splitbrake band therein, an abutment arranged between the ends of said band,arigid segment'on said band intermediate the ends thereof, guiding meansintermediate said abutment and said rigid segment for holding saidflexible brake band adjacentsaid brake drum, and means for directlyapplying outward radial pressure to said rigid segment.

a flexible internal split brake band therein,

12. The combination with a brake drum, of

an abutment between the ends of said band, a.

point to provide separable ends and con-- structed to anchor on eitherof said ends, and

having at least one rigid segment and an adj a cent flexible segment.

14. A brake member comprising a ring cut through at one point to provideseparable ends and constructed to anchor on either of said ends, andhaving a plurality of flexible portions and an interposed rigid portion.

.' 15. A friction device for a brake comprising an expansible ring cutthrough at one point to provide separable ends and adapted to anchor ateither of said ends, and which is reinforced to be substantially rigid.in at least one segment not more than 180 long,

" the ring as a whole being expansible.

16. A brake comprising, in combination, a

drum, :1 floating band which has an intermediate segment substantiallyrigid and which is substantially flexible on opposite sides of saidsegment, and an abutment against which one of-the ends of the bandanchors when the drum is turning in one direction and against which theother of said ends anchors when the drum is turning in the otherdirection.

17. A brake comprising, in combination, a

drum, a floating expansible band which as a -whole is substantiallyflexible but which nevertheless has a rigid segment, and anchoring meansengaged by one part of said band other than said segment when the drumis turning in one direction and by a different part of said band whenthe drum is turning in the-other direction.

'18. A brake comprising, in combination, a drum, a floating expansibleband within the drum which is reinforced at' least in one segment to besubstantially rigid, an anchoring abutment between the ends of the band,and

- two positiomng. devices on opposite sides of a center line passingthrough saidiabutment and which co operate with the abutment indetermining the released position of the band.

' 19. The combination with a brake drum, of a flexible internal splitbrake band therein, an

abutment arran ed between and taking the braking torque om the ends ofsaid band, a portion of said band intermediate said ends beingreinforced to render it substanfl sithe hand against the drum.

tially rigid, and applying means for forcing 20'. The combination witha-brake drum, of

a flexible internal split brake band thereiil, an abutment arrangedbetween and taking the braking torque from the ends of said band, asingle portion of said band of considerable length being reinforced torender it substantially rigid, and applying means for forcing the bandagainst the drum.

21. The combination with a brake drum, of

floating expansible friction means shiftable bodily with the drum andhaving adjacent separable ends, applying means for forcing the frictionmeans against the drum, and

torque-taking means operated by the shifting .of the friction means toforce said ends apart to increase the braking pressure.

22. The combination with a brake drum, of floating expansible frictionmeans shiftable bodily with the drum and having adjacent separable ends,applying means for forcing the friction means against the drum, and anabutment between said ends moved by the shifting of the friction meansto force said ends apart to increase the braking pressure.

23. A brake comprising floating friction means having separable ends, incombination with torque-taking means engaging said ends and operated bythe torque of the brake to force said ends apart and brake-appl ingmeans separate from said torque-ta 'ng means.

24. A brake comprising a drum and fioat- I ing friction means havingseparable ends, in combination with a torque-taking abutment pivotedadjacent said ends and swung by the torque of the brake to force saidends apart in either direction of rotation of the drum.

25. In a brake mechanism, a rotatable drum, braking means thereforcomprising a circular split band having a rigid primary portion and aflexible secondary portion, said primary portion engaging said drum toapply braking force to substantially all of said secondary portion.

26. In a brake mechanism, a rotatable drum, braking meansthereforcomprising integral rigid primary and flexible secondaryportions, substantially all of said flexible portion being expanded toengage said drum by the frictional engagement of said primary portionwith said drum.

27. In a brake mechanism, a rotatable drum, braking means thereforcomprising a. circular flexible split band having a rigid reinforcingmember extending around a portion of the circumference thereof, andactuating means for engaging said reinforced portion of said. band withsaid drum whereby movement of said reinforced portion with said drumforces substantially all of the flexible portion of said braking meansto engage said drum to retard rotation thereof.

28. Ina brake mechanism, a rotatable drum, a brake engageable therewithhaving integral rigid primary and flexible secondary portions, and meansfor moving said primary III portion into engagement with said drum, saidengagement of said primary portion with said drum expandingsubstantially all of said flexible secondary portion into frictional en-5 gagement with said drum.

29, In a brake mechanism, a rotatable drum, a brake therefor comprisingintegral rigid primary 'and flexible secondary portions, means formoving said rigid primary 5 portion into contact with said drum toexpand the majorv portion of said flexible secondary portion tofrictionally engage said drum, and means to prevent rotation of saidsecondary portion. q 30. In a brake mechanism, a rotatable drum, a brakeengageable therewith having 7 integral rigid and flexible portions, astop for i the ends of said brake, and means for mov-, ing said rigidportion to engage said drum, movement of said portion with said drumexpanding substantially all of said flexible portion to engage saiddrum, said stop preventing rotation of said brake.

31. In a brake mechanism, a rotatable drum, a brake engageable therewitheompris-,

ing a flexible bandand a rigid member secured to the inner face thereofand extending for a portion of the length of said band, a stop for theends of said band to limit the movement thereof relative to said drum,and means for moving the rigid portion of said band into engagement withsaidvdrum, rotation of said rigid portion expanding substantially all ofthe flexible portion of said band to engage said drum. p 32. In a brakemechanism, a rotatable drum, braking means engage'able, therewith havinga rigid portion and a flexible portion integral with said rigid portion,means con- 40 nected to the rigid portion intermediate the ends of saidbraking means for moving said rigid portion toengage saiddrum, therebyexpanding.sulistantially all ofsaid flexible portiont-d engage said drumand means for 45. preventing rotation of said braking means. "QALANSONP.,BRUSH.

